Dredger-cutter.



No. 856,544. PATBNTED JUNE 11,1907.

I J. F. OLLRIOH. DREDGER CUTTER. APPLICATION FILED AUG 21 1906 2 SHEETS-SHEET 2.

IN VEN TOR. 1 a. m 54 W WITNESSES:

ATTORNEY.

UNITED STATES PATENT OFFICE.

DREDGER-CUTTER.

Specification of Letters Patent.

Patented June 11, 1907.

Application filed A t 21,1906. Serial No. 331,476.

To all whom it may concern:

Be it known that I, JOHN F. OLLRICH, a citizen of the United States,residing at San Francisco, in the county of San Francisco andState of California, have invented new 'and useful Improvements in Dredger-Cut ters, of which the following is a specification.

This invention relates to cutter heads and teeth therefor for dredging machines, the object of the invention being to provide cutter heads and teeth which will be more effective than those heretofore employed, .and will be less expensive in repair and mainte nance.

In the accompanying drawings, Figure 1 is a side view of one form of my improved cutter head; Fig. 2 is a broken end view of the same; Fig. 3 is an enlarged longitudinal section of one of the cutter bars; Fig. 4 is an end view of the bar 3 Fig. 5 is a section of the same Fig. 6 is a front view showing a modification of the invention; Fig. 7 is a side view of another modification; Fig. 8 is a broken end view of the same; Fig. 9 is a longitudinal section of one of the cutter bars; Fig. 10 is a longitudinal section of one of the teeth Fig. 11 is a perspective view of the tooth.

Referring to the drawing, 1 indicates the shaft of the cutter head, having secured thereonthe hub 2, from which radiate the arms or. spokes 3, upon the ends of which are formed the bars 4, all lying in a skew surface of revolution, that is, in planes oblique to that through the shaft, and also extending farthest from the shaft at the end farthest from the hub 2. Secured to said bars are the enlarged bases 5 of teeth 6, bolts 7 being used to secure the plates to the bar.

In the form of the invention illustrated in Figs. 1 to 3, a single plate is used for each bar, while in the modification shown in Fig. 6 two plates are provided for each bar. This division may be carried to a greater extent, if necessary, so that there may be an independent plate for each tooth, or each pair of teeth, or other plurality thereof.

The essential feature of this invention is the plate or base formed integral with the tooth, resting on the bar and removably secured thereto. The plate takes the wear caused by the abrasion of the material being cut, and thus saves the bar from wear. These plates and teeth can be renewed at a comparatively small expense when worn, and

the bar itself, being protected from wear by abrasion, lasts for an indefinite period.

In the modification shown in Figs. 7 to 11 a separate plate is provided for each tooth, and these plates do not fit close to each other. This close fit is not, however, necessary in this case, as the bars will still be protected from wear by the plates. In this modification the combined tooth and plate is shown as having a socket and driven on to a post or projection 9 extending from the bar. In order to facilitate the removal of the teeth the bar is formed with transverse holes 10 through which a tool can be inserted to drive the tooth from off the post. In the latter modification the numbers of teeth on adjacent bars differ by one, and since the teeth are uniformly spaced on the bars this causes each tooth to cut in a path between the cuts of two teeth on the preceding bar, insuringrapid and effective work by the cutter.

I claim 1. A cutter head comprising a shaft, a hub thereon, arms or spokes radiating from said hub, bars extending from the ends of said arms or spokes, and teeth having enlarged bases resting upon the bars, and protecting them from wear by abrasion, said teeth and bars being provided with means for removably securing them together, substantially as described.

2. A cutter head comprising a shaft, ahub thereon, arms or spokes radiating from said hub, bars extending from the ends of said arms or spokes, and teeth having enlarged bases resting upon the bars, and protecting them from wear by abrasion, said teeth and bars being provided with. means removably securing them together, said teeth being uniformly spaced on the bars and the numbers of teeth on adjacent bars differing by one, substantially as described.

3. A cutter head comprising a shaft, a hub thereon, arms or spokes radiating from said hub, bars extending from the ends of said arms or spokes, and teeth having enlarged bases resting upon the bars, and rotecting them from wear by abrasion, and so having sockets, and the bars having posts or rojections engaging said sockets, substantially as described.

4. A cutter head comprising a shaft, a hub thereon, arms or spokes radiating from said.

hub, bars extending from the ends of said In testimony whereof I have hereunto set arms or spokes, and teeth having enlarged my hand in the presence of two subscribing 10 bases resting upon the bars, and protecting Witnesses.

them from Wear by abrasion and also having a T sockets, and the bars having posts or pro- JOHN QLLRICH' jections engaging said sockets, and having WVitnesses:

also apertures behind said plates 01' bases, 7 F. M. WRlGHT,

substantially as described. B. NAGGS. 

